Swine Flu vs. Canine Flu: Similarities and Differences

The Influenza A virus infects both pigs and dogs. Flu symptoms of swine flu and canine flu can include fever, runny nose, coughing, lethargy and loss of appetite. In some cases, the flu also causes nausea and diarrhea. Severe complications include secondary infections and death. Coughing and sneezing of saliva into the air spreads the flu virus, as does passing infected objects from organism to organism.

First isolated from a pig in 1930, swine flu has mixed with human and avian flu strains to create new viral strains that are not confined to one species. Swine flu is now the focus of international concern because it has spread from pig to human, and human to human, sparking predictions of an eventual pandemic. There are vaccines for human flu, and one for swine flu is under development in the wake of the outbreak in April 2009.

Identified in 2005, canine flu originated when a strain of equine flu "jumped species" and caused the illness in greyhound dogs. Since then, canine flu has been shown to infect other breeds as well; it can cause severe damage to the respiratory system. Canine flu spreads from dog to dog, and cannot infect humans or swine. Swine flu cannot infect canines. There is no vaccine yet for canine flu.